org.jivesoftware.openfire.pubsub.LeafNode Maven / Gradle / Ivy
/*
* Copyright (C) 2005-2008 Jive Software. All rights reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.jivesoftware.openfire.pubsub;
import java.util.ArrayList;
import java.util.Date;
import java.util.HashSet;
import java.util.List;
import java.util.Set;
import java.util.UUID;
import java.util.concurrent.atomic.AtomicLong;
import org.dom4j.Element;
import org.jivesoftware.util.LocaleUtils;
import org.jivesoftware.util.cache.CacheFactory;
import org.xmpp.forms.DataForm;
import org.xmpp.forms.FormField;
import org.xmpp.packet.IQ;
import org.xmpp.packet.JID;
import org.xmpp.packet.Message;
/**
* A type of node that contains published items only. It is NOT a container for
* other nodes.
*
* @author Matt Tucker
*/
public class LeafNode extends Node {
private static final String genIdSeed = UUID.randomUUID().toString();
private static final AtomicLong sequenceCounter = new AtomicLong();
/**
* Flag that indicates whether to persist items to storage. Note that when the
* variable is false then the last published item is the only items being saved
* to the backend storage.
*/
private boolean persistPublishedItems;
/**
* Maximum number of published items to persist. Note that all nodes are going to persist
* their published items. The only difference is the number of the last published items
* to be persisted. Even nodes that are configured to not use persitent items are going
* to save the last published item.
*/
private int maxPublishedItems;
/**
* The maximum payload size in bytes.
*/
private int maxPayloadSize;
/**
* Flag that indicates whether to send items to new subscribers.
*/
private boolean sendItemSubscribe;
/**
* The last item published to this node. In a cluster this may have occurred on a different cluster node.
*/
private PublishedItem lastPublished;
// TODO Add checking of max payload size. Return plus a application specific error condition of values;
String booleanValue;
if ("pubsub#persist_items".equals(field.getVariable())) {
values = field.getValues();
booleanValue = (values.size() > 0 ? values.get(0) : "1");
persistPublishedItems = "1".equals(booleanValue);
}
else if ("pubsub#max_payload_size".equals(field.getVariable())) {
values = field.getValues();
maxPayloadSize = values.size() > 0 ? Integer.parseInt(values.get(0)) : 5120;
}
else if ("pubsub#send_item_subscribe".equals(field.getVariable())) {
values = field.getValues();
booleanValue = (values.size() > 0 ? values.get(0) : "1");
sendItemSubscribe = "1".equals(booleanValue);
}
}
@Override
void postConfigure(DataForm completedForm) {
List values;
if (!persistPublishedItems) {
// Always save the last published item when not configured to use persistent items
maxPublishedItems = 1;
}
else {
FormField field = completedForm.getField("pubsub#max_items");
if (field != null) {
values = field.getValues();
maxPublishedItems = values.size() > 0 ? Integer.parseInt(values.get(0)) : 50;
}
}
}
@Override
protected void addFormFields(DataForm form, boolean isEditing) {
super.addFormFields(form, isEditing);
FormField typeField = form.getField("pubsub#node_type");
typeField.addValue("leaf");
FormField formField = form.addField();
formField.setVariable("pubsub#send_item_subscribe");
if (isEditing) {
formField.setType(FormField.Type.boolean_type);
formField.setLabel(
LocaleUtils.getLocalizedString("pubsub.form.conf.send_item_subscribe"));
}
formField.addValue(sendItemSubscribe);
formField = form.addField();
formField.setVariable("pubsub#persist_items");
if (isEditing) {
formField.setType(FormField.Type.boolean_type);
formField.setLabel(LocaleUtils.getLocalizedString("pubsub.form.conf.persist_items"));
}
formField.addValue(persistPublishedItems);
formField = form.addField();
formField.setVariable("pubsub#max_items");
if (isEditing) {
formField.setType(FormField.Type.text_single);
formField.setLabel(LocaleUtils.getLocalizedString("pubsub.form.conf.max_items"));
}
formField.addValue(maxPublishedItems);
formField = form.addField();
formField.setVariable("pubsub#max_payload_size");
if (isEditing) {
formField.setType(FormField.Type.text_single);
formField.setLabel(LocaleUtils.getLocalizedString("pubsub.form.conf.max_payload_size"));
}
formField.addValue(maxPayloadSize);
}
@Override
protected void deletingNode() {
}
public synchronized void setLastPublishedItem(PublishedItem item)
{
if ((lastPublished == null) || (item != null) && item.getCreationDate().after(lastPublished.getCreationDate()))
lastPublished = item;
}
public int getMaxPayloadSize() {
return maxPayloadSize;
}
public boolean isPersistPublishedItems() {
return persistPublishedItems;
}
public int getMaxPublishedItems() {
return maxPublishedItems;
}
/**
* Returns true if an item element is required to be included when publishing an
* item to this node. When an item is included then the item will have an item ID
* that will be included when sending items to node subscribers.
*
* Leaf nodes that are transient and do not deliver payloads with event notifications
* do not require an item element. If a user tries to publish an item to a node
* that does not require items then an error will be returned.
*
* @return true if an item element is required to be included when publishing an
* item to this node.
*/
public boolean isItemRequired() {
return isPersistPublishedItems() || isPayloadDelivered();
}
/**
* Publishes the list of items to the node. Event notifications will be sent to subscribers
* for the new published event. The published event may or may not include an item. When the
* node is not persistent and does not require payloads then an item is not going to be created
* nore included in the event notification.
*
* When an affiliate has many subscriptions to the node, the affiliate will get a
* notification for each set of items that affected the same list of subscriptions.
*
* When an item is included in the published event then a new {@link PublishedItem} is
* going to be created and added to the list of published item. Each published item will
* have a unique ID in the node scope. The new published item will be added to the end
* of the published list to keep the cronological order. When the max number of published
* items is exceeded then the oldest published items will be removed.
*
* For performance reasons the newly added published items and the deleted items (if any)
* are saved to the database using a background thread. Sending event notifications to
* node subscribers may also use another thread to ensure good performance.
*
* @param publisher the full JID of the user that sent the new published event.
* @param itemElements list of dom4j elements that contain info about the published items.
*/
public void publishItems(JID publisher, List itemElements) {
List newPublishedItems = new ArrayList<>();
if (isItemRequired()) {
String itemID;
Element payload;
PublishedItem newItem;
for (Element item : itemElements) {
itemID = item.attributeValue("id");
List entries = item.elements();
payload = entries.isEmpty() ? null : (Element) entries.get(0);
// Make sure that the published item has a unique ID if NOT assigned by publisher
if (itemID == null) {
itemID = genIdSeed + sequenceCounter.getAndIncrement();
}
// Create a new published item
newItem = new PublishedItem(this, publisher, itemID, new Date(CacheFactory.getClusterTime()));
newItem.setPayload(payload);
// Add the new item to the list of published items
newPublishedItems.add(newItem);
setLastPublishedItem(newItem);
// Add the new published item to the queue of items to add to the database. The
// queue is going to be processed by another thread
if (isPersistPublishedItems()) {
PubSubPersistenceManager.savePublishedItem(newItem);
}
}
}
// Build event notification packet to broadcast to subscribers
Message message = new Message();
Element event = message.addChildElement("event", "http://jabber.org/protocol/pubsub#event");
// Broadcast event notification to subscribers and parent node subscribers
Set affiliatesToNotify = new HashSet<>(affiliates);
// Get affiliates that are subscribed to a parent in the hierarchy of parent nodes
for (CollectionNode parentNode : getParents()) {
for (NodeSubscription subscription : parentNode.getSubscriptions()) {
affiliatesToNotify.add(subscription.getAffiliate());
}
}
// TODO Use another thread for this (if # of subscribers is > X)????
for (NodeAffiliate affiliate : affiliatesToNotify) {
affiliate.sendPublishedNotifications(message, event, this, newPublishedItems);
}
}
/**
* Deletes the list of published items from the node. Event notifications may be sent to
* subscribers for the deleted items. When an affiliate has many subscriptions to the node,
* the affiliate will get a notification for each set of items that affected the same list
* of subscriptions.
*
* For performance reasons the deleted published items are saved to the database
* using a background thread. Sending event notifications to node subscribers may
* also use another thread to ensure good performance.
*
* @param toDelete list of items that were deleted from the node.
*/
public void deleteItems(List toDelete) {
// Remove deleted items from the database
for (PublishedItem item : toDelete) {
PubSubPersistenceManager.removePublishedItem(item);
if (lastPublished != null && lastPublished.getID().equals(item.getID())) {
lastPublished = null;
}
}
if (isNotifiedOfRetract()) {
// Broadcast notification deletion to subscribers
// Build packet to broadcast to subscribers
Message message = new Message();
Element event =
message.addChildElement("event", "http://jabber.org/protocol/pubsub#event");
// Send notification that items have been deleted to subscribers and parent node
// subscribers
Set affiliatesToNotify = new HashSet<>(affiliates);
// Get affiliates that are subscribed to a parent in the hierarchy of parent nodes
for (CollectionNode parentNode : getParents()) {
for (NodeSubscription subscription : parentNode.getSubscriptions()) {
affiliatesToNotify.add(subscription.getAffiliate());
}
}
// TODO Use another thread for this (if # of subscribers is > X)????
for (NodeAffiliate affiliate : affiliatesToNotify) {
affiliate.sendDeletionNotifications(message, event, this, toDelete);
}
}
}
/**
* Sends an IQ result with the list of items published to the node. Item ID and payload
* may be included in the result based on the node configuration.
*
* @param originalRequest the IQ packet sent by a subscriber (or anyone) to get the node items.
* @param publishedItems the list of published items to send to the subscriber.
* @param forceToIncludePayload true if the item payload should be include if one exists. When
* false the decision is up to the node.
*/
void sendPublishedItems(IQ originalRequest, List publishedItems,
boolean forceToIncludePayload) {
IQ result = IQ.createResultIQ(originalRequest);
Element pubsubElem = result.setChildElement("pubsub", "http://jabber.org/protocol/pubsub");
Element items = pubsubElem.addElement("items");
items.addAttribute("node", getNodeID());
for (PublishedItem publishedItem : publishedItems) {
Element item = items.addElement("item");
if (isItemRequired()) {
item.addAttribute("id", publishedItem.getID());
}
if ((forceToIncludePayload || isPayloadDelivered()) &&
publishedItem.getPayload() != null) {
item.add(publishedItem.getPayload().createCopy());
}
}
// Send the result
service.send(result);
}
@Override
public PublishedItem getPublishedItem(String itemID) {
if (!isItemRequired()) {
return null;
}
synchronized (this) {
if (lastPublished != null && lastPublished.getID().equals(itemID)) {
return lastPublished;
}
}
return PubSubPersistenceManager.getPublishedItem(this, itemID);
}
@Override
public List getPublishedItems() {
return getPublishedItems(getMaxPublishedItems());
}
@Override
public synchronized List getPublishedItems(int recentItems) {
List publishedItems = PubSubPersistenceManager.getPublishedItems(this, recentItems);
if (lastPublished != null) {
// The persistent items may not contain the last item, if it wasn't persisted anymore (e.g. if node configuration changed).
// Therefore check, if the last item has been persisted.
boolean persistentItemsContainsLastItem = false;
for (PublishedItem publishedItem : publishedItems) {
if (publishedItem.getID().equals(lastPublished.getID())) {
persistentItemsContainsLastItem = true;
break;
}
}
if (!persistentItemsContainsLastItem) {
// And if not, include the last item.
publishedItems.add(0, lastPublished);
// Recheck the collection size, it might have one more element now (the last item).
// Remove it, if it exceeds the max items.
if (publishedItems.size() > recentItems) {
publishedItems.remove(publishedItems.size() - 1);
}
}
}
return publishedItems;
}
@Override
public synchronized PublishedItem getLastPublishedItem() {
if (lastPublished == null){
lastPublished = PubSubPersistenceManager.getLastPublishedItem(this);
}
return lastPublished;
}
/**
* Returns true if the last published item is going to be sent to new subscribers.
*
* @return true if the last published item is going to be sent to new subscribers.
*/
@Override
public boolean isSendItemSubscribe() {
return sendItemSubscribe;
}
void setMaxPayloadSize(int maxPayloadSize) {
this.maxPayloadSize = maxPayloadSize;
}
void setPersistPublishedItems(boolean persistPublishedItems) {
this.persistPublishedItems = persistPublishedItems;
}
void setMaxPublishedItems(int maxPublishedItems) {
this.maxPublishedItems = maxPublishedItems;
}
void setSendItemSubscribe(boolean sendItemSubscribe) {
this.sendItemSubscribe = sendItemSubscribe;
}
/**
* Purges items that were published to the node. Only owners can request this operation.
* This operation is only available for nodes configured to store items in the database. All
* published items will be deleted with the exception of the last published item.
*/
public void purge() {
PubSubPersistenceManager.purgeNode(this);
// Broadcast purge notification to subscribers
// Build packet to broadcast to subscribers
Message message = new Message();
Element event = message.addChildElement("event", "http://jabber.org/protocol/pubsub#event");
Element items = event.addElement("purge");
items.addAttribute("node", nodeID);
// Send notification that the node configuration has changed
broadcastNodeEvent(message, false);
}
}